Technical Issues Associated with Deep Repositories for Radioactive Waste in Different Geological Environments

21 Oct 2009

As part of its better regulation science programme the Environment Agency has recently published a report written by Quintessa.

The aim of the study was to select a set of geological environments to represent the range of plausible repository host environments in England and Wales that might be identified through the Government's MRWS process, and to identify the main technical issues that would need to be considered when evaluating the safety of a repository in each of the environments.

The following broad technical issues were identified:

influence of different wasteform types on the design of the engineered barrier system (EBS)

interactions between engineered components

interactions between the EBS and the host rock

impact of groundwater/porewater on EBS materials (including the impact of saline water)

duration for which EBS materials maintain their function (durability)

interactions between gas and groundwater (or porewater)

characterising the site adequately

demonstrating long-term stability

impact of repository resaturation

It was concluded that the design of a repository should be matched to the characteristics of its host geological environment. When designing a repository, it is necessary to take into account the highly coupled nature of many processes. Most issues associated with the performance of EBS materials under repository conditions are reasonably well understood.

A summary of the project (354 KB) and the full report (2.77 MB) are available here.